EP 0136155 B1 19891115 - SINGLE-CHIP MICROCOMPUTER COMPRISING MEANS FOR PREVENTING READ-OUT OF ITS INTERNAL ROM
Title (en)
SINGLE-CHIP MICROCOMPUTER COMPRISING MEANS FOR PREVENTING READ-OUT OF ITS INTERNAL ROM
Publication
Application
Priority
JP 17597783 A 19830922
Abstract (en)
[origin: US5067077A] A single-chip microcomputer connectable to an external memory for expanding the address space, and having a first mode of operation in which the available memory region is both the region of an internal ROM and the external memory, and having a second mode of operation in which the available memory region is the region of the external memory only. An inhibiting device is provided for inhibiting the switching from the second mode to the first mode, thereby ensuring that the contents of the internal ROM cannot be read-out.
IPC 1-7
IPC 8 full level
G06F 1/00 (2006.01); G06F 12/06 (2006.01); G06F 12/14 (2006.01); G06F 15/78 (2006.01); G06F 21/12 (2013.01); G06F 21/22 (2006.01); G06F 21/75 (2013.01); G06F 21/86 (2013.01)
CPC (source: EP KR US)
G06F 12/0623 (2013.01 - EP US); G06F 12/14 (2013.01 - KR); G06F 12/1433 (2013.01 - EP US); G06F 12/0638 (2013.01 - EP)
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
US 5067077 A 19911119; DE 3480499 D1 19891221; EP 0136155 A2 19850403; EP 0136155 A3 19861217; EP 0136155 B1 19891115; JP H0228179 B2 19900621; JP S6068441 A 19850419; KR 850002911 A 19850520; KR 890001312 B1 19890429
DOCDB simple family (application)
US 67166091 A 19910319; DE 3480499 T 19840919; EP 84306405 A 19840919; JP 17597783 A 19830922; KR 840005730 A 19840919